Monday March 24th, NMRWA staff toured the Pittsburgh Water and Sewer Authority (PWSA) treatment plant facility. NMRWA has several connections to PWSA, in addition to our shared interest in regional water quality: Sara Madden, StormWorks Design Manager, is a member of their Green Infrastructure Technical Advisory Committee, and James Stitt, PWSA Sustainability Coordinator, is a member of the NMRWA Board of Directors.
Starting our tour with a brief history of potable water treatment and transportation in Pittsburgh, Gina Cyprych, PWSA’s Environmental Compliance Coordinator, described how Pittsburgh’s water needs have shifted over time.
Beginning in the late 1700s and 1800s, most of the focus was on building an adequate water supply, in part to help prevent fires like the great fire of 1845 that destroyed nearly 1/3 of the city.
It wasn’t until 1894 however that Pittsburgh began to focus more on water treatment than water capacity. This was spurred by extremely high death rates from both cholera and typhoid in the mid-1800s. John Snow’s proof of a relationship between cholera and drinking water supply in 1855 also helped to demonstrate the need for water filtration.
Over the next twenty years, a slow sand filtration plant was constructed, as well as multiple reservoirs, storage tanks, and pumping stations. These improvements, along with chlorine disinfection caused cholera and typhoid rates to drop dramatically.
Since PWSA was formed in 1984, they have continued to make improvements to their water treatment process – the slow sand filters have been replaced with new, more efficient technologies, and PWSA is beginning to focus on sustainability and green technologies, in addition to maintaining excellent water quality. (Just a note: the former Pittsburgh Water Department became a part of PWSA in 1995.)
Today, PWSA services more than 300,000 people with over 100 million gallons of water a day, and a lot of work goes into treating that much water!
It is first pumped from the Allegheny River, and then goes through a multi-step process of filtration and treatment before it is pumped to several water towers and reservoirs throughout the city. One unique feature of PWSA’s infrastructure is that all of the water its customers receive is gravity fed – there is no pumping necessary after it reaches those reservoirs.
Thank you so much to Gina and PWSA for the tour! We enjoyed learning more about PWSA and the important work they do.